A research team from the University of Cincinnati Cancer Institute recently developed a new oral vaccine that produces a novel immune system defense against cancer cells, particularly against the recurrence of breast cancer.

Jason Steel, the first author of the study, and his team of UC and National Institutes of Health researchers developed the oral breast cancer vaccine from a recombinant adeno-associated virus. Unlike prior cancer vaccines developed from bacteria, AAV is a virus that has minimal negative effects on human health.

"AAV is special because the virus survives the stomach," Steel said. "Normally, you introduce a virus by mouth and it is broken down in the stomach. This virus is resistant to breakdown, which opened up the possibility of administering it orally as a cancer vaccine."

In a preclinical animal study published on January 8 in the journal Molecular Therapy, the researchers found that the AAV vaccine produced both short-term and long-term impact on the reduction of breast cancer tumors. The team said that the AAV-based vaccine could potentially serve as a human breast cancer prevention tool.

"We have done similar studies with different virus strains that have produced an antibody response," Steel said. "With this virus, we get both an antibody and a tumor-killer T-cell response. By combining the two mechanisms of action in one vaccine, we are creating a two-pronged immune system attack on the cancer cells that appears to be more effective."

Later this year, the UC team will start testing the AAV-based oral vaccine for the prevention of other cancers such as lung cancer.